Prime and composite numbers. Prime factors
Answers are for parents and teachers.
1
Write 5 primes below 100 and say why each is prime.
For example 11, 19, 43, 61, 97: each divides only by 1 and itself.
2
Factor 48 into primes.
2⁴ · 3
3
Compute 2 · 3 · 5 · 7.
210
4
Find the sum of primes from 1 to 30.
129
5
Why are all primes except 2 odd?
Even numbers are divisible by 2, so they have a divisor other than 1 and themselves.